Sometimes there is a group that gets it right away, and runs with it, but it usually takes some time.
There are usually a few who think they are smarter than average (they usually are), that their intelligence will compensate (it rarely does), and that they don't need to make any extra effort. They usually figure it out after a semester.
I also had a class mutiny once. I had a couple of intelligent, but spoiled and opinionated students who were vocally critical of my/this instructional style. There was also a larger than usual number of dullards in the class, who were easily led (by the dissenters). The self-nominated leaders managed to turn most of the class' attitude sour. That was the worst semester I've had yet. Everything became difficult. I had trouble maintaining my own discipline.
The real trick that I would like to learn, is how to turn more of the middle and bottom tier of students into better students.